The plasmaspheric effects on the maintenance of the nighttime ionosphere

Abstract

The plasmasphere, or the inner magnetosphere is a region of the Earth's magnetosphere consisting of low energy plasma. It is located above the ionosphere and dynamically interact with it along the magnetic field lines. During the daytime, the ions in the ionosphere, produced by solar EUV radiation, are diffused upward along the magnetic field lines at mid-latitudes and become the main source of the plasmaspheric plasma density. During the nighttime, however, the ions in the plasmasphere can diffuse downward to the ionosphere where the significant parts of the ionospheric density are depleted by the recombination with neutrals. In order to study the effects of this downward plasma transport on the nighttime ionosphere, we utilized the total electron content (TEC) data measured from the JASON satellite from 2002 to the current. This satellite measures not only the ionospheric TEC from the ground to the satellite orbit altitude (1336 km) but also the plasmaspheric TEC by the dual-frequency GPS receiver aboard the satellite. We analyzed these ionospheric and plasmaspheric TEC measurements for different seasons and solar activities to study the contribution of the plasmaspheric TEC to the maintenance of the nighttime ionospheric TEC.